Cutter chain and method of assembly

ABSTRACT

A CUTTER CHAIN AND METHOD OF ASSEMBLY THEREFOR EMPLOYING PINTLES HAVING PORTIONS NON-ROTATIVELY RETAINED WITHIN CUTTER CARRYING LINKS AND A RECESSED CENTRAL PORTION ALONG ONE SIDE TO ALLOW SPACE FOR GREATER THAN NORMAL SPROCKET TOOTH SIZE RELATIVE TO A GIVEN PITCH LENGTH.

Sept. 20 1971 w, E I 3,605,514

CUTTER CHAIN AND METHOD OF ASSEMBLY Filed April 8. 1969 INVENTOR. Rulpfi w Mltcfieu.

3,605,514 Patented Sept. 20, 1971 U.S. Cl. 74-254 Claims ABSTRACT OF THE DISCLOSURE A cutter chain and method of assembly therefor employing pintles having portions non-rotatively retained within cutter carrying links and a recessed central portion along one side to allow space for greater than normal sprocket tooth size relative to a given pitch length.

The present invention relates to cutter chains such as those used in coal cutters and ripper chain mining machines, which chains are made up of a plurality of saddle type bit carrying links alternating with and connected together by insertion type connector links. All of said links being flexibly attached to adjacent links by pintles nonrotatively held in a bit link and rotatively engaged by adjacent connector links. The cutter chains of this invention are quite similar to those shown and described in U.S. Patent 2,956,442 (Krekler).

The cutter chain of this invention is of novel design giving rise to the following advantages:

The pintle of this invention provides for easier assembly of links and connectors than was possible with recessed pins of the prior art because the design of the pintle of this invention although providing a recessed central portion does provide on that same side of the pintle a continuous fiat surface opposed to a diametrically opposite smooth cylindrical surface so that at no point in the insertion of the pintle is there looseness between the bit link openings and the pintle being inserted.

These and other advantages and objects of this invention will become more readily apparent upon consideration of the following description and drawings in which:

FIG. 1 is a three-dimensional oblique view at approximately full size of a pintle constructed according to the principles of this invention;

FIG. 2 is a sectional view taken substantially on line 22 of FIG. 1;

FIG. 3 is a smaller scale side elevational view of a portion of a cutter chain constructed according to the principles of this invention;

FIG. 4 is a sectional view taken substantially on line 4-4 of FIG. 3;

FIG. 5 is an enlarged fragmentary sectional view taken substantially on line 55 of FIG. 4.

Referring now to the drawings, FIG. 3 shows a portion of a cutter chain generally indicated at comprising a plurality of cutter bit links 12 and connector links 14 flexibly fastened together by pintles 16 to form a flexible chain in a manner well known in the art. The bit links 12 are provided with bit receiving sockets (not shown) and suitable bit fastening means such as set screws (also not shown) in a well known manner. The bit links 12 are of the saddle type having at each end thereof a pair of cheeks 13 spaced apart to receive one end of the connector 14 between the cheeks 13 at either end of the bit link 12. The pair of cheeks 13 at one end of a bit link 12 have respective coaxial openings 18 therein of noncircular outline shown as D-shaped with a flat surface 19 on the side of the opening nearest the center line of the respective link.

Extending through the cheek openings 18 and slidably received therein are the pintles 16 having D-shaped end portions 20 having major surface portions 20' of circularly curved outline combined with coplanar flat surface portions 21 so that the end portions 20 are of the same shape as the cheek openings 18 and the pintles 16 are non-rotatively held by the cheeks 13 due to the non-circular nature of the cheek openings 18 and the end portions 20 are preferably dimensioned to form a driving fit with the cheek openings 18 to retain the pintles 16 in the respective bit link. The curved portions 20 have a common axis 16' considered to be the central axis of the pintle 16.

The central portion 24 of the pintle 16 has four surface portions as hereinafter described. A surface portion 24' amounting to approximately one-half of the surface of the central portion 24 (to to the left as seen in FIGS. 1 and 2) is simply a coaxial continuation of the circular portions 20' of the end surface portions 20 earlier described. Another portion of the central surface portion 24 is a narrow flat portion 26 (to the right in FIGS. 1 and 2) best seen in FIG. 1 as a narrow continuation of the coplanar end flats 21 and extending therebetween. The remainder of the surface of the central portion 24 comprises two portions of at least one cylindrical surface, shown as upper and lower recessed curved portions 38 and 39, respectively, which are formed on a radius approximately equal to or slightly smaller than the radius of the circularly curved surface portions 20' of the end portions 20 and on an axis 30 parallel to axis 16 and spaced to the left thereof as seen in FIG. 2. Recessed surfaces 38 and 39 have circumferentially spaced edges joined together by the axially coextensive flat surface 26. The forming of the surfaces 38 and 39 develops inwardly facing shoulders 27 between the end portion surfaces 20' and the respective surface 38 and 39. The flat surfaces 21 are the exterior surfaces of a sector of the pintle 16 having a dihedral angle of approximately for example, while the recessed surfaces 38 and 39 together with the fiat surface 26 form the exterior surface of a sector of the pintle 16 having a dihedral angle of approximately which sector includes the sector of the flats 21. The utility of this four-part surface will be made plain in conjunction with the following description.

Each of the connector 14 is provided with a circular bore 31 of substantially the same diameter as the circular portion 20' of the pintle end portion 20 but enough larger to provide clearance for a sliding fit of the end portion 20 through the connector bore 31. Thus, when the connector end is between the cheeks 13 and a pair of openings 18 are aligned with a bore 31 the pintle 16 is inserted through one of the openings 18, through the connector bore 31 and the other opening 18 by simple straight sliding action while simultaneously maintaining non-rotative contact between the fiat side 19 of a bit link opening 18 and the flat 26 due to full spacing of flat 26 from the diametrically opposite curved surface 24', to assemble a connector link 14 with a bit link 12. Once this assembly has been accomplished the normal tension of the chain, wherever installed, will cause a connector 14 to move to the left as seen in FIG. 5 bringing the connector :14 and the pintle 16 into the relationship there shown. The axial length of the central surface portion 24 being slightly greater than the thickness of the connector 14 will allow the connector 14 to move into the positive shown.

The utility of the central portion flat 26 resides in the fact that the flat 26- is at the same distance from the back surface 24 of the central portion 24 as are the flat surfaces 21 from the back side of the end surface portions 20" so that even though the central portion surfaces 38 and 39 are recesed below the surfaces 20' of the end portion 20 there are still two continuous supporting areas, namely the flats 21 with the central portion flat 26 and the end surface portions 20- with the backside 24 of the central portion 24 suitably spaced to be slidable within the cheek openings 18 and keep the pintle aligned as it passes through one of the cheek openings 18 and across the space between the cheeks to enter the second cheek opening 18. With the central portion flat 26' sliding along the flat 19 of the cheek opening 18 there is no position at which the pintle 16 is loose in the opening 18 or can become directionally or rotatively misaligned as normally happens with a recessed pin of the prior art.

It is to be noted that with a pintle of approximately one and one-half inch diameter at the end the flat portion 21 will have a width of approximately 71 while the central portion flat 26 has a width of approximately 7 For this same size pin the displacement of the axis 30 to the left of the axis 16 (as viewed in FIG. 2) will be of the order of /s. With such dimensioning it has been found that the above described relationship will be developed with the stated advantages resident therein.

The above dimensions are given by Way of example but the exact amount of any dimension is not critical as long as each dimension is suitably proportioned to the other dimensions of the particular pintle to give the above described relationships among the bit links, connectors and pintles.

FIG. shows the application of the principles of this invention in a second embodiment comprising the continuous flat 26 in combination with the two axis recessed portions 28 and 29 more completely described and illustrated in copending application Ser. No. 812,758 filed Apr. 2, 1969 (McDowell) with the axes 28' and 29 respectively for the surfaces 28 and 29 as described therein. With the fiat surface 26 separating the parallel axis surfaces 28 and 29 we have the formation of a pintle 36 applying the principles of this invention with the additional advantages residing in the two axis surfaces as set forth in the above identified McDowell application as well as the advantages residing in the feature of recessed surface or surfaces on the same side of the pintle as the fiat surface as set forth in application Ser. No. 812,759 filed Apr. 2, 1969 (Rollins). It is to be realized that any combination of the features set forth in the Rollins and McDowell applications (both assigned to the same assignee as is this application) with the central flat surface of this application is envisioned as an embodiment of the principles of this invention.

Preferred embodiments of this invention having been hereinabove described it is to be realized that variations in the application of the principles of this invention can be applied without departing from the principles of this invention. It is therefore respectfully requested that this invention be interpreted as broadly as possible.

What is claimed is:

1. A pintle comprising a body member having: axially spaced end portions and a central portion intermediate said end portions; said central portion having an exterior surface extending axially thereof along one side thereof; said exterior surface having recessed surface portions formed as two portions of at least one cylindrical surface having at least one axis spaced from and parallel to the central axis of the pintle; said two portions having spaced edges joined by a flat surface portion extending axially of the pintle; and each of said end portions having at least a flat surface joined to and coplanar with said flat surface portion.

2. A pintle as specified in claim 1 wherein said recessed surface portions are portions of two separate intersecting cylindrical surfaces of substantially equal radius having spaced apart axes parallel to the central axis of said pintle and substantially equidistant therefrom.

3. A pintle as specified in claim 2 wherein the distance between the spaced axes of said separate cylindrical surfaces is less than the distance of said spaced axes from said central axis.

4. A pintle as specified in claim 3 wherein the end portions of said pintle have at least major surface portions of circular cylindrical shape and said two separate cylindrical surfaces of said recessed portion have equal radii approximately equal to the radius of said end surface major portions.

5. A cutter chain pintle as specified in claim 1 wherein the common plane of said flat surfaces is parallel to said central axis.

References Cited UNITED STATES PATENTS 2,788,670 4/1957 Bruestle 74251 2,826,085 3/1958 Cartlidge 74-254 2,956,442 10/1960 Krekeler 74-254 CORNELIUS I. HUSAR, Primary Examiner 

